President Reagan continued during this past week to make his point: The United States possesses military power and he is ready and willing to use it. On Tuesday and Wednesday, US naval vessels fired on Syrian positions in the Lebanese mountains above Beirut. And on Wednesday and Thursday, the battleship New Jersey fired its guns toward anti-US forces.
But another point was also being made. For every move Reagan makes in what is verging on an undeclared war against Syria, there is a possible countermove. On Dec. 12 a Muslim fanatic drove his truck bomb into the US Embassy compound in Kuwait. It reminded everyone of the Oct. 23 truck bombing of the US Marine base in Beirut, when 240 marines were killed.
Also during the week the US raised its estimate of the number of Soviet military personnel in Syria from 7,000 to 8,000. Defense Secretary Caspar Weinberger stated that they included ''organized troop units.''
There is not the slightest indication that US readiness to use force is persuading Syria to withdraw its forces from Lebanon or stopfiring at US reconnaissance planes flying over Syrian positions in Lebanon.
Nor is there evidence that even the guns of the world's only commissioned battleship discourage the Soviets from putting more of their military power into Syria.
At time of writing, the only important Soviet action of the week on the world scene was to have the Soviet delegation at the conventional arms talks in Vienna leave those talks without agreeing to a return date. This follows the Soviet delegations' leaving both the strategic nuclear arms and the European theater negotiations without setting return dates.
In other words, the Soviets have closed down the three main arenas for a continuing dialogue with the West. There are other, technical discussions which continue in a desultory way, but nothing of major importance to the future stability of the world. In effect, there is no longer any substantive discussion going on between Washington and Moscow.
The presumed purpose of the use of US military power in Lebanon is to obtain the withdrawal of Syrian forces. This would clear the way for the official government of Lebanon, led by Amin Gemayel, to extend its authority over the entire country and make peace with Israel.
Mr. Reagan addressed the US Medal of Honor Society in New York Dec. 12 and told his audience: ''We have tried turning our swords into plowshares, hoping others would follow. Well, our days of weakness are over. Our military forces are back on their feet and standing tall.''
Those military forces had completed an earlier assignment successfully. The last combat units came off Grenada during the week. A few technical people remained for cleanup work left over from the invasion that began Oct. 25.
That use of military force seems to have eliminated Cuban and Soviet influences from the island while rescuing US citizens, clearing the way for Grenada's return to democracy, and restoring the island as a resort for tourists.
But in Lebanon the US marines continue to dig deeper into the earth to escape shelling from Lebanese elements dissatisfied with the Gemayel regime and hence unfriendly to the protection the Marine presence gives to that regime. And two US aircraft carriers, plus the USS New Jersey, all with accompanying smaller craft, patrol off the coast in support of the marines and of US purposes in Lebanon.
Meanwhile, up in the hills above Beirut and the marines, the Syrians and their allies strengthen their positions and the Soviets strengthen the Syrians.
Mideast experts, led by Joseph Sisco who was the State Department's senior expert on the area, have been advising the White House to open direct negotiations with Syria. This week special US Mideast envoy Donald Rumsfeld visited Damascus for talks with Syrian leaders.
The outcome of the talks was not immediately visible. The Syrians have stated they intend to continue firing at US aircraft that fly over their positions in Lebanon. And Mr. Reagan says the reconnaissance flights are necessary to protect US marines.
Among the experts there was questioning about whether Mr. Reagan had worked out a logical connection between his purposes and his actions.
High Washington officials insist there is no intention to attack Syria itself. It is difficult to see how a limited approach of bombing and shelling Syrian positions in Lebanon will induce the Syrians to leave Lebanon or prevent Druze and Shiite factions from shooting at the marines.
So, as things stand, Mr. Reagan has made his point. Everyone knows now that he commands military force and is willing to use it. But is it of any use in Lebanon?